The application claims priority to German Application No. 10 2004 044 670.9, which was filed on Sep. 15, 2004.
The invention relates to a vehicle body panel part, particularly to a vehicle roof panel, having an outer part defining at least a portion of an outer skin, an inner layer formed on a rear side of the outer part, and an elongated, tubular hollow body embedded in the inner layer.
Body panel parts for a vehicle are parts that are mounted to a vehicle body to define, at least in sections, an outer skin of the vehicle in a final assembled state, and which are visible from outside the vehicle. Body panel parts may be flaps (doors, covers), bumpers or roof modules. Roof modules include vehicle roof panels or covers for roof opening systems.
It is already known to produce foamed vehicle body panel parts such as roof modules or flaps from plastic, such as a glass fiber-reinforced polyurethane (PU) material for example. Glass fiber portions are introduced in the plastic by a long fiber injection (LFI) method, for example.
Document DE 196 37 793 C1 discloses a glass cover of a roof opening system which is back foamed with PU material, with filling bodies being encased in foam and completely consisting of polyurethane, polystyrene or plastic. An open profile, which is also encased in foam, is intended to contribute to the reinforcement. Glass fiber portions are not included in the PU material.
EP 0 598 352 B1 discloses elongated and upwardly open insert pieces of a glass cover of a roof opening system that are embedded in the back foaming. These insert pieces are inserted in a biased state and thus stiffen the glass cover. This provides a desired curvature in a simple manner.
Due to different material strengths of an inner layer and the associated different expansion and shrinking behavior in certain sections of the vehicle body panel parts, an impairment of the surface quality can occur in the vehicle body panel parts.